淬火介质对2519铝合金抗晶间腐蚀性能的影响  

Effect of quenching agent on intergranular corrosion resistance of 2519 aluminum alloy

作　　者：李慧中[1,2] 梁霄鹏[1] 卫晓燕[1] 王海军[1] 刘洪挺[1] 郭菲菲[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中南大学有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2010年第2期123-128,共6页Materials Science and Engineering of Powder Metallurgy

基　　金：国家重点基础研究发展规划(973计划)资助项目(2005CB623706);中南大学博士后基金资助项目(2007-8);中国博士后基金资助项目(20070420828)

摘　　要：2519铝合金热轧板在530℃下保温2 h后,分别于室温(20℃)水、机油和空气中淬火,经10%冷轧变形后,于180℃进行人工时效。通过显微硬度测试、金相显微镜和透射电镜观察以及动电位极化曲线的测试,研究淬火介质对2519铝合金抗晶间腐蚀性能的影响。结果表明:经空气淬火的合金晶界析出第二相,晶界析出相粒子粗大,呈不连续分布,无沉淀析出带宽度为130 nm,晶间腐蚀深度为300μm;经室温水淬和机油淬火并时效后,晶界上的析出相尺寸较小,呈链状分布,无沉淀析出带宽度分别为20 nm和30 nm。经室温(20℃)水淬火的合金未发生晶间腐蚀,经机油淬火的合金只发生局部点蚀,说明经室温水淬的合金比经空气和机油淬火的合金时效后具有更好的抗晶间腐蚀性能。2519 aluminum alloy hot-rolled sheets were kept at 530 ℃ for 2 h and quenched in water,oil and air at room temperature（20 ℃）,respectively.Then the sheets were deformed at the rate of 10% and aged at 180 ℃.The effects of quenching agent on intergranular corrosion resistance of 2519 alloy were investigated by means of hardness tests,optical microscope（OM）,potention dynamic polarization and transmission electron microscopy（TEM）.The results show that： The grain boundary precipitates are coarse and discontinuous observed,the width of the precipitation free zone（PFZ） is 130 nm when the peak-aged alloy quench in air.The grain boundary precipitates are refinement and chain,the width of the PFZ are 20 nm and 30 nm when the peak-aged alloys quench in the water and oil at room temperature.The depth of intergranular corrosion is 300 μm after quenching in air,it shows pit corrosion after quenching in oil and there is no intergranular corrosion after quenching in room temperature water（20 ℃）.The peak-aged alloys quenched in water and oil have better intergranular corrosion resistance than that of alloys quenched in air.

关 键 词：2519铝合金 淬火介质 显微组织 晶间腐蚀 

分 类 号：TG292[金属学及工艺—铸造]